Effects of Cattle Dung on the Behavior and Survival of Adult Screwworms 1 and on the Development of their Eggs

Abstract
Fifty-six percent of sterile adult screwworms, Cochliomyia hominivorax (Coquerel), collected with a sweep net from cattle dung and vegetation at cattle-congregating areas in South Texas were mated females. No mating activity was observed at these sources. Collections from a wind-oriented trap baited with swormlure-2 and from dung yielded 3.7 and 11.6% males, respectively; these sex ratios were considered similar enough to suggest that some chemical components of swormlure-2 and dung may be related. Aging of dung reduces its attractiveness. Dung contributes little to screwworm survival and is an inadequate nutritional source for egg development in the second gonotrophic cycle. Dung may aid females in locating potential hosts.